This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. A bead-angiogenesis model is implanted in fibrin hydrogels of varied stiffness in this study. They are furthermore treated with actin contractility inhibitors. Angiogenic vessel sprouts that develop on the beads are then analyzed in terms of actin contractility presence as well as morphological differences. The tissues are stained for actin as well as CD31 to determine the effects of contractility inhibition on capillary morphogenesis.